Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Robotic devices may be used for many applications, and may operate in a variety of environments. Such robotic devices may need to operate in environments with a sloped ground, an environment with rocky terrain, or various other uneven landscapes. In such environments, the robotic device may need to know the slope of the ground to maintain balance and to progress forward. Such robotic devices may include systems to estimate a flat-plane approximation of the shape of the ground on which the robotic devices are walking in order to move across such terrains.